<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <title>Vue Custom Directive Demo</title>
</head>
<body>
<div id="app">
  <input v-model="item" type="text">
  <div v-square="item"></div>
</div>
<script src="https://cdnjs.cloudflare.com/ajax/libs/vue/2.0.3/vue.js"></script>
<script src="script.js"></script>
</body>
</html>